Wind Driven Power Generator with Moveable Cam

ABSTRACT

A wind driven generator includes a rotor disposed in a cylindrical duct and supported by a frame for rotation in response to wind flowing through the duct. The rotor includes plural circumferentially spaced paralleled rotor blades supported for rotation about a generally horizontal axis. Each blade is supported for pivotal movement to change blade pitch, angle of attack or camber as the rotor rotates. A pitch or camber control motor, self-governing wind vane mechanism, or governing mechanism is operable to move a circular cam to vary blade pitch or camber to control rotor speed. The duct is mounted on a mast having a base supported on a foundation for pivotal movement to face the wind for maximizing air flow through the duct. Electric power generators are connected to opposite ends of the rotor at respective power output or drive shafts.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation-in-part application ofco-pending U.S. Non-Provisional patent application Ser. No. 11/505,966,filed Aug. 17, 2006, and a non-provisional patent application of U.S.Provisional Patent Application No. 61/031,317, filed Feb. 25, 2008, bothwhich are hereby incorporated by reference in their entirety.

BACKGROUND

Wind driven power generators are under intensive development as energyneeds and the costs associated therewith continue to escalate. With thedevelopment of wind driven power generators certain needs have becomeapparent, including the need to provide a generator which overcomes thedisadvantage of conventional airscrew or propeller type generators whichmust be mounted at a substantial height above the surface, are notaesthetically pleasing, are a hazard to airborne wildfowl, and aresusceptible to ice accumulation on the propeller blades.

There has been a continuing need and desire for improvements in winddriven power generators, including the desire to overcome theshortcomings of conventional power generators such as those describedhereinabove, while also providing a generator which is efficient,physically compact and is easily adapted to varying wind velocityconditions while retaining the capability of power generation. It is tothese ends, as well as other desiderata and needs which will be apparentto those skilled in the art, that the present invention has beendeveloped.

SUMMARY

The present invention provides an improved wind driven power generator.

The present invention also provides a wind driven power generator whichincludes a unique rotor or propeller configuration, is compact and lessobtrusive than conventional airscrew or propeller type generators andincludes a rotor which may be disposed within a shroud or duct forefficiency improvements while minimizing hazards to bird life and whilebeing less susceptible to performance degradation or structural problemsassociated with ice or snow accumulation, for example.

In accordance with an important aspect of the present invention, a winddriven power generator is provided with a rotor having circumferentiallyspaced airfoil shaped blades which are arranged in a circular patternnot unlike a so-called paddle wheel and which have a mechanismassociated therewith for varying the “lift” of the rotor blades toprovide a resultant driving force in response to wind flowing thereover.Thus, the blades effect rotation of the rotor to provide a usefulresult, such as driving an electric power generator.

In accordance with another important aspect of the present invention, awind driven power generator is provided which includes a rotor which ischaracterized by a unique multi-blade pitch change mechanism for varyingblade pitch or angle of attack as the blades rotate about an axisgenerally parallel to the blade length. The multi-blade rotor may beadapted to be connected to one or two electric power generators, orother power generating devices, and the speed of the rotor may becontrolled to provide for variable power output and/or at a selectedelectrical energy characteristic.

In accordance with still another important aspect of the presentinvention, a wind driven power generator is provided which includes arotor comprising rotor blades which have an airfoil shape and whereinthe camber or curvature of the airfoil maybe varied. In this way the“lift” forces exerted by the rotor blades or vanes may be selectivelyconverted into a resultant useful force for driving the rotor. Anarticulated rotor blade configuration, together with a blade camberchange mechanism, provides the useful resultant force of the rotorexerted by the blades as the rotor rotates

In accordance with yet a further aspect of the invention, a wind drivenpower generator is provided which includes rotor speed control meansincluding an embodiment which is self-governing in relation to thevelocity of wind flowing over the rotor.

In accordance with yet a further aspect of the present invention a winddriven power generator is provided wherein a rotor which is responsiveto wind flowing thereover rotates within a duct or shroud to improverotor efficiency, and minimize the adverse effects of rain, or snow orice accumulation on the rotor or flow of such through the duct. The ductis particularly advantageous in that there are provided paths for theflow of cooling air over one or more electric generators connected tothe rotor. Still further, the rotor duct or shroud is preferablyconfigured to accelerate the flow of air through the duct and the ductis also configured to modify or improve the weather vaning tendency ofthe generator so that the duct opening is normally oriented to takeadvantage of the direction of the wind.

Those skilled in the art will further appreciate the above-mentionedadvantages and superior features of the invention together with otherimportant aspects thereof upon reading the detailed description whichfollows in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one preferred embodiment of a winddriven power generator in accordance with the invention;

FIG. 2 is a perspective view similar to FIG. 1 showing certain detailsof the power generator rotor and its support structure;

FIG. 3 is a detail section view taken generally along the line 3-3 ofFIG. 2;

FIG. 4 is a cutaway perspective view showing a portion of the rotorsupport structure and the rotor pitch change control mechanism;

FIG. 4A is a detail view taken from line 4A-4A of FIG. 4;

FIG. 5 is a detail section view taken generally along the line 6-6 ofFIG. 4;

FIG. 6 is a detail section view taken generally along the line 6-6 ofFIG. 4;

FIG. 7 is a detail section view taken generally along the line 7-7 ofFIG. 6;

FIG. 8 is a detail section view similar to a portion of FIG. 6 but on alarger scale to illustrate the configuration of one of the cam followersand its connection with the rotor pitch change control linkage;

FIG. 9 is a somewhat schematic view of the rotor blades showing thepositions of the blades in a so-called full stall condition of therotor;

FIG. 10 is a view similar to FIG. 9 but showing the angle of attack orpitch of the rotor blades in a so-called zero angle or maximumperformance condition;

FIG. 11 is a top plan view of another preferred embodiment of a rotorfor a wind driven power generator in accordance with the invention;

FIG. 12 is a side-elevation of the rotor embodiment shown in FIG. 11;

FIG. 13 is a perspective view of a modified rotor and bladeconfiguration including blade camber change mechanism in accordance withanother preferred embodiment of the present invention;

FIG. 14 is a detail section view taken generally along the line 14-14 ofFIG. 13.

FIG. 15 is a partial sectional perspective view of the wind turbinepower generator with a modified cam with the governor mechanism in anintermediate position;

FIG. 16 is a sectional view of the cam and governing mechanism shown inFIG. 15;

FIG. 17 is a section view of the cam and governing mechanism shown inFIGS. 15 and 16 with the governor mechanism rotated outwardly;

FIG. 18 is a partial sectional view of the governor mechanism and amodified cam with a variation of the cam groove that is shown in FIGS.15 through 17;

FIG. 19 is a detailed partial sectional view of the turbine powergenerator shown in FIG. 16; and

FIG. 20 is a sectional view of the modified cam of FIGS. 15 through 17and 19 without the governor mechanism.

DETAILED DESCRIPTION

In the description which follows, like parts are marked throughout thespecification and drawings with the same reference numerals,respectively. The drawing figures may not be to scale and certainfeatures may be shown exaggerated in scale or in somewhat schematic formin the interest of clarity and conciseness.

Referring to FIG. 1, there is illustrated a wind driven power generatorin accordance with the invention and generally designated by the numeral20. The power generator 20 is characterized by a vertically extendingmast 22, preferably having a symmetrical airfoil shape in cross section,and supporting a generally cylindrical duct or shroud 24. Duct 24 has anair inlet 26 defining an opening oriented to allow natural air currentsor wind to flow through said opening for propelling or driving a rotor,generally designated by the numeral 28. Rotor 28 may be of a typesimilar to that disclosed and claimed in my co-pending U.S. patentapplication Ser. No. 11/411,540 filed on Apr. 26, 2006, the subjectmatter of which is incorporated herein by reference. However, the rotor28 is adapted for rotation about a substantially horizontal axis withinthe duct 24 in response to natural air currents or wind flowing throughthe duct. Mast 22 is mounted on a generally cylindrical base member 30which is supported for rotation on a foundation member 32. An axis ofrotation of the mast 22 with respect to foundation member 32 isindicated at 33 and such axis is disposed closer to a leading edge 22 aof mast 22 than a trailing edge 22 b. In this way the mast 22 will tendto weathervane or rotate such that the duct inlet opening 26 is alignedwith the direction of wind blowing over the generator 20. Base 30supports the mast 22 for relatively free rotation on foundation 32 bysuitable bearing means interposed the base and the foundation.

Referring to FIG. 2, the generator 20 is further characterized by aframe 36 including a generally upstanding column member 38 disposedwithin and connected to mast 22 but extending downwardly through thebase 30 and the foundation 32 to a suitable bearing or receptacle 37disposed below grade and within an earth formation 38, as illustrated.Receptacle 37 and frame 36 are electrically conductive and serve toconduct any cloud-to-ground or ground-to-cloud lightning which mayaffect operation of the generator 20.

Frame 36 includes a substantially horizontally extending arm 40supporting spaced apart upstanding frame members 42 and 44 which areadapted to support rotor 28 in a manner to be described in furtherdetail herein. Respective lightning rods 41 and 43, FIG. 2, arepreferably provided mounted on frame members 42 and 44. As shown in FIG.2, rotor 28 is drivingly connected to spaced-apart opposed electricgenerators 46 and 48 whereby electricity generated by the generators 46and 48 may be conducted by conductor means 47 and 49 via a junction box50 and further conductor means 51 and 52 to a power takeoff or slip ringassembly disposed on and between the base 30 and the foundation 32. Asillustrated in FIG. 2, concentric slip rings 54 and 56 on foundation 32are adapted to receive power from brushes 54 a and 56 a mounted on base30 and connected to conductor means 51 and 52, for example.

Referring now to FIG. 3, further details of the duct 24 are illustratedincluding a preferred configuration wherein the duct includes an outer,generally cylindrical shroud member 60 generally spaced from butdisposed in supportive relationship with an inner, generally cylindricalshroud member 62. Shroud or duct member 62 is characterized by a venturishaped wall defining a throat or minimum diameter section 62 a at whichrotor 28 is disposed, generally. At least portions of shroud member 62are spaced from shroud member 60, as shown, to provide opposedlongitudinal passages 61 and 63 which have air inlet openings at 61 aand 63 a at the duct inlet 26 and exhaust openings at 61 b and 63 bdownstream of rotor 28 with respect to the direction of wind flowthrough the duct 24, which wind flow direction is indicated by the arrow65 in FIG. 3. Accordingly, generators 46 and 48 are disposed within therespective cooling air flow passages 63 and 61 whereby heat generatedduring operation of the generators may be dissipated by a natural flowof ambient air through the passages 61 and 63. As shown in FIGS. 1 and3, outer duct member 60 is also provided with spaced apart rearwardlyprojecting vanes 60 a which assist the mast 22 in orienting the duct 24to be aligned with the direction of wind. Secondary cooling air inlets61 c and 63 c may be provided in the inner duct or shroud member 62, asindicated also in FIG. 3.

Referring now to FIGS. 4, 4A, 5 and 6, the rotor 28 is mounted forrotation on the support members 42 and 44 by respective shaft members 70and 72, FIGS. 5 and 6, which are also directly connected to therespective electric generators 46 and 48. In FIG. 4 the generator 46 isomitted for the sake of clarity and the generators 46 and 48 have beenomitted from the illustrations of FIGS. 5 and 6 also for clarity andconvenience. The rotor 28 is characterized by spaced-apart assemblies ofcircumferentially spaced, radially extending arms or spokes, whichassemblies are designated by numerals 74 and 76, respectively. Armassemblies 74 and 76 are characterized by circumferentially spaced,radially extending airfoil shaped tubular arm or spoke members 78 whichare equally spaced and are each connected to a hub 79, see FIGS. 5 and6. Hubs 79 are mounted on shafts 70 and 72 for rotation therewith,respectively. As shown in FIGS. 5 and 6, shafts 70 and 72 are supportedin suitable rolling element bearing assemblies 71 mounted in suitablebores in the respective frame support arms 42 and 44. The support arms78 of the respective arm assemblies 74 and 76 are aligned with eachother and are operable to support therebetween elongated airfoil shaped,generally parallel, rotor blades 80, which total eight in number for therotor 28. Rotor blades 80 include a leading edge 80 a and a trailingedge 80 b, respectively, FIG. 7. For a rotor having eight blades 80, theblades, preferably, have an aspect ratio in a range of 6:1 to 20:1 and asymmetrical airfoil shape although other airfoil shapes, such asprovided by a variable camber blade, may be suitable. For a sixteenblade rotor, the aspect ratio may be in a range of 4:1 to 15:1. Rotorblades 80 are mounted for pivotal movement on the respective arms 78substantially at the distal ends of the arms, as illustrated in FIG. 7,and whereby each end of each rotor blade 80 is mounted at a pivot 81.Rotor blades 80 are mounted at their opposite ends at pivots 81 of eachtubular arm 78 of the respective are assemblies 74 and 76 as shown byexample in FIG. 7.

The rotor 28 includes rotor blade “lifting” force control meansdescribed herein below. Referring further to FIG. 7, in one preferredembodiment, each arm 78 of arm assembly 74 is also provided, generallyat its radially inward end with elongated slots 83 for receivingsuitable cam followers 88 to be described further herein. Cam followers88 are each, respectively, connected to an elongated blade pitch changelink 84. Links 84 are disposed within the hollow interiors of therespective arms 78 and are connected at their outer distal ends to theblades 80 at pivot connections 85, respectively, and whereby, inresponse to generally linear longitudinal movement of the links 84, thepitch angle or angle of attack of the respective blades 80 and, hence,the blade lift forces may be varied in accordance with the teaching ofthe above-referenced patent application Ser. No. 11/411,540.

Referring to FIG. 6, there is illustrated the inner ends of two of thelinks 84 and connected to two respective cam followers 88. Cam followers88 are also disposed partially in a circular groove or recess 90 formedin a generally circular or cylindrical disk cam member 92 mounted on hub79 but disposed on suitable bearing means 93 to allow rotation of thehub 79 relative to the cam 92, see FIG. 4A also. As shown further inFIG. 4A, circular groove 90 of cam 92 has a central axis 73 a which isparallel to but eccentric with respect to the axis of rotation 73 of theshafts 70 and 72. Axis 73 is also indicated in FIGS. 5 and 6,respectively. Cam 92 is connected to a gear 96, FIG. 6, which is meshedwith a pinion 98 connected to the output shaft 100 of a motor 102 whichis adapted to rotate the cam 92 into selected positions to effectvarying the pitch or angle of attack of the blades 80 with respect tothe direction of the wind flowing through the duct 24 as the rotor 28rotates about axis 73. By selectively varying the pitch or angle ofattack of the rotor blades 80, the generator 20 may efficiently utilizewind flow through duct 24 to rotate the rotor 28 and generate electricalpower by way of the respective generators 46 and 48.

Referring briefly to FIG. 5, the shaft 72, on which hub 79 for armassembly 76 is mounted, also supports for rotation therewith a brakedisk 106 which is operable to be engaged by a suitable caliper mechanism108 to brake the rotation of the rotor 28 to control the rotative speedthereof so as to effectively generate electricity, for example, with thegenerators 46 and 48 at a selected frequency as well as at apredetermined power output. Accordingly, the motor 102 may be operatedto rotate the cam 92 to selected positions for changing the angle ofattack or pitch of the rotor blades 80 while the rotor 28 may also becontrolled as to its speed of rotation about the axis 73, as desired,independent of the effects of blade pitch control.

Referring briefly to FIG. 8, details of one of the cam followers 88 areillustrated. Cam followers 88 each include a generally cylindricalfollower part 88 a disposed within the groove 90 of cam 92 for traversaltherein. A shank 88 b extends axially from the follower part 88 a. Pitchcontrol links 84 each include a transverse pivot sleeve part 84 a formedthereon and including a bore 84 b adapted to receive the cam followershank 88 b. Generally cylindrical annular guide members 88 d are sleevedover the shank 88 b, journaled on the transverse link part 84 a and areretained in assembly with the link 84, as illustrated, by a threaded nut88 c. Members 88 d are of a diameter slightly less than the width of thegrooves or slots 83 for guidance therewithin.

Referring now to FIG. 9, there is illustrated a condition of the rotor28 wherein the blades 80 are disposed in positions corresponding to aso-called full stall condition wherein blade “lift” forces and a netresultant force acting on the rotor by wind flowing through the ductinlet 26 in the direction of arrow 65 will not effect rotation of therotor. This is one limit position of the cam 92 as it is rotated by thedrive motor 102. FIG. 10, on the other hand, shows a condition of therotor 28 wherein the blades 80 have assumed positions, respectively,which will produce a maximum resultant force tending to turn the rotorin a clockwise direction, viewing FIG. 10 in response to air flowing inthe direction of arrow 65. Exemplary blade angles with respect to winddirection, indicated by arrow 65, for the rotor positions shown in FIGS.9 and 10 one indicated in the drawing figures. The clockwise directionof rotation of the rotor 28 about the axis 73 is also indicated by thearrow 99 in FIG. 10. In FIGS. 9 and 10, the rotor blade angles indicatedare, of course, for the particular positions of the respective blades80, as illustrated, and the pitch angles vary continuously with respectto arms 78, for example, as the rotor 28 rotates.

Referring now to FIGS. 11 and 12, an alternate embodiment of a powergenerator in accordance with the invention is illustrated showing amodification to the control mechanism for changing the pitch or angle ofattack of the rotor blades 80. In FIGS. 11 and 12 there is illustratedthe rotor assembly 28 drivingly connected to the generators 46 and 48and supported on the arms 42 and 44 of the support frame 36. However, inthe embodiment illustrated in FIGS. 11 and 12, the circular cam 92 hasbeen replaced by a modified version of the cam, generally designated bythe numeral 92 a. Cam 92 a is supported for rotation about axis 73 andits circular cam groove is also eccentric with respect to that axis. Cam92 a is also supported on the shaft 70 in generally the same manner asillustrated in FIG. 6.

The power generator embodiment illustrated in FIGS. 11 and 12 includes aself-governing wind vane assembly 110 including a transversely extendingairfoil or vane 112 supported on spaced-apart arms 114 and 116. Arm 114is connected to cam 92 a and arm 116 is preferably mounted for rotationon and with respect to hub 79 of arm assembly 76 adjacent brake disk106. Accordingly, the wind vane assembly 110 is free to rotate aboutaxis 73 within the limits of an arc, as indicated by the arrow 113 inFIG. 12, for example. As the vane assembly 110 rotates in a clockwisedirection, viewing FIG. 12, the cam 92 a is rotated to a position whichwill tend to move the pitch of the rotor blades 80 in a direction whichwill result in less of a resultant force tending to rotate the rotor 28in a clockwise direction, viewing FIG. 12. Accordingly, as wind velocityincreases, in the direction of the arrow 65 in FIGS. 11 and 12, thepitch change control mechanism of the embodiment illustrated, beingself-governing, will tend to reduce the resultant force effectingrotation of the rotor 28 and thus control the speed and output effort ofthe rotor. In all other respects the embodiment illustrated in FIGS. 11and 12 is substantially like the embodiment illustrated in FIGS. 1through 10.

Referring now to FIGS. 13 and 14 another embodiment of the invention isillustrated wherein a modified rotor 28 c is characterized by variablecamber blades 80 c, a portion of one being shown in both FIGS. 13 and14. Variable camber blade 80 c includes interconnected blade sections 80d, 80 e and 80 f which are hingedly connected to each other at hingestructure including an elongated hinge boss 130, FIG. 14, formed on thefront or leading edge blade section 80 d. Hinge boss 130 is fitted in arecess formed by opposed arcuate rim portions 132 and 134 formed onintermediate airfoil or blade section 80 e. A second set of arcuate rimportions 136 and 138 extend parallel to the rim portions 132 and 134 anddefine a second recess for receiving a hinge boss 140 of trailing edgeblade section 80 f. Accordingly, the blade sections 80 d, 80 e and 80 fare adapted for limited pivotal movement with respect to each otheralong axes parallel to the longitudinal axis of blade 80 c whereby thecamber of blade 80 c may be varied between its leading edge 144 and itstrailing edge 146, as shown in FIGS. 13 and 14. Variable camber blade 80c is mounted between opposed blade end section members 148, one shown inFIG. 13, and is pivotally connected thereto at pivot 81 formed onleading edge section 80 d and a pivot member 81 b projecting from theside edge of trailing edge section 80 f. Pivot 81 b is slidable in aslot 149 formed in blade end section 148 as shown in FIG. 13.

Referring further to FIG. 13, intermediate blade section 80 e includes alongitudinally projecting tab part 151 which is slideable in a slot 153extending substantially normal to the chord line of variable camberblade 80 c. Accordingly, variable camber blade 80 c may be mounted onrotor arms 78, one shown in FIG. 13, in place of the blade 80 andconnected to link 84 at a pivot connection formed by a hexhead shoulderscrew 84 e, FIG. 13, disposed in a suitable bore 131 formed in hingeboss 130 of leading edge section 80 d, see FIG. 14. Accordingly, as therotor 28 c rotates the camber of the 80 c varies to vary the lift forcesexerted by the respective blades 80 c by selectively changing theconfiguration of the airfoil formed by the blades 80 c wherein anairfoil configuration having a substantial amount of positive camber, asillustrated in FIG. 14, may be changed to an airfoil actually havingnegative camber, as indicated in FIG. 13. Although FIG. 14 is takengenerally along the line FIG. 14-14 of FIG. 13 the condition of theblade 80 c shown in FIG. 14 is with the blade having substantialpositive camber. In the condition of the blade 80 c shown in FIG. 13,the blade has somewhat negative camber. As shown in FIG. 13, a suitablerecess or slot 154 is formed in blade end section 148 to accommodatemovement of the fastener 84 e interconnecting the link 84 with theleading edge section 80 d of rotor blade 80 c. Thus, the lifting forcesexerted by a series of blades 80 c used in place of the blades 80 arevaried as a rotor 28 c rotates due to the action of the linkages 84selectively moving the blades 80 c to change their airfoil configurationor camber whereby the resultant driving force of rotor 28 c may beprovided and varied.

In the embodiment illustrated in FIGS. 15 through 20, a mechanism 156 isprovided for governing the rotational velocity of the turbine 20 tomaximize its efficiency and to reduce undesirable strain that may beobserved at undesirable wind velocities, particularly where excessiveturbulence arises. Referring to FIGS. 15 through 19, governing mechanism156 comprises an arm 158 and a linkage 160 that is operably connected tothe cam 92. The governing mechanism arm 158 includes a first end or head162 and a curved second end or tail 164, and the first end as shown isenlarged relative to the second to provide a greater mass. It iscontemplated that the first end can be made of a more dense materialthan the second end so that both ends could be of similar size. The massof the first end relative to the second may be varied upon thesensitivity desired for modulating the rotational velocity of the rotor.The tail 164 of the arm has an “L”-shaped portion 166 forming a pivotpoint 170 and linkage attachment end 172, where the pivot point issecured to an extension 168 of the arm member and the linkage attachmentend is connected to the linkage that is in turn connected to the cam.The linkage attachment end, as shown in FIG. 15, and in more detail inFIG. 20, preferably has a receiving slot 173 for a fastener 174, such asa bolt as shown, although any suitable fastener known to one of ordinaryskill is acceptable. The linkage 160 has two ends that can be referredto as an arm attachment end 176 and a cam attachment end 178. The armattachment end, like the arm's linkage attachment end 172, as shown, mayalso include a receiving slot for accepting a fastener. In theembodiment illustrated in FIG. 15, the cam attachment end 178 includes ahead portion 180 having an outwardly projecting ring or overhang 182that fits into a gap or slot 184 in a side of the cam central recess 186although the cam attachment end may be attached to the cam by anysuitable means known to one of ordinary skill in the art. The linkageextends through the hub 79 and holds arm member 78 against the cam 92.As the arm member rotates faster about the shaft 70, the arm head 162 ofthe governor mechanism 156 moves outwardly with respect to shaft 70about arrow 157 via centrifugal forces causing the second end or tail164 causing relative displacement of the cam 92 in relation to the armassembly. Although a multiplicity of governor mechanisms is shown inFIG. 15, and opposing pairs shown in FIGS. 16 and 17, a continuous ringfixedly attached to the arm member is acceptable, as well as anysymmetrically positioned arrangement about the hub's circumference, tomitigate weight imbalances is suitable.

Further discussion of cam follower 88 and cam groove 90 is now made withreference to FIGS. 15 through 20. As noted, the arm assembly isconnected for adjustable rotor blade angle of attack and is accessiblein elongated slot 83 at its proximal end via cam follower 88 whichdepends substantially normally from the proximal end of the armassembly. Cam follower 88 includes a cam follower interface or head 188(shown as a partially spherical body or ball) for fitted engagement ofcam groove 90 formed in the cam 92. As shown in FIGS. 16 through 20, theinterface 188 (substantially similar to cam follower part 88 a discussedreferred to above) has a central opening that cam follower 88 extendstherethrough so as to receive a fastener 190 that holds the interface inposition relative to the cam follower. The interface may rotate aboutthe cam follower or it may be fixedly attached thereto, or the camfollower and the interface may integrally formed.

In the embodiment illustrated in FIGS. 15 through 20, modified camgrooves are shown. Referring to FIGS. 15 through 17 and 20, thelongitudinal axis 194 of cam groove 90 is at an angle relative to thetransverse axis 196 of cam 92. With reference to FIGS. 16 through 20,the angle is more than zero degrees but less than 90 degrees in thefirst quadrant in a rectangular coordinate system where the Y-axis isthe side of cam 92 having cam groove 88 and the X-axis is axis 196.Alternatively, the relative movement to the governor mechanism bringsthe cam 92 closer to the arm member, causing the cam follower to moveupwardly and inwardly as it travels in the cam groove. The upwardmovement of the cam follower 188 effects movement of the rotor bladesvia the control means and arm assembly to vary the pitch angle andcamber of the rotor blades. Another embodiment of the cam groove isillustrated in FIGS. 18 and 19 forming a composite or modified angledcam groove having a varying surface. The varying cam groove comprises atleast one angled portion that has a longitudinal axis parallel to axis194 and a second transverse portion having a longitudinal axissubstantially parallel to the transverse axis of the cam.

In another embodiment that is illustrated, shown in FIG. 21, the camgroove is angled as shown in FIGS. 15, 16 and 17, although it mayinclude the modified cam groove of FIGS. 18 and 19, but need not includethe governor mechanism described above. Referring to FIG. 21, anopposing force against the arm assembly is provided by mechanicaltensioning device 200, such as a spring (shown) or deformable bearings,between the cam and the hub of the arm member. As the rotation of thearm member increases, the centrifugal forces of the rotation causes thearm assembly to move outwardly with respect to the shaft 70, forcing thecam 92 to move closer to the arm member with the effect of the camfollower moving upwardly and inwardly within the cam groovesubstantially as described above causing the arm assembly via link 84,as before, to vary the pitch angle and camber of the rotor blades inorder to reduce rotation of rotor 20. Tensioning device 200 provides anopposing force against the cam as the cam moves closer to the armassembly. Tensioning device 200 is located in FIG. 21 between thesupport and the cam. One of ordinary skill in the art will appreciatethat the turbine's wind environment may be considered when determiningthe desired tension.

The construction and operation of the power generator embodimentsdescribed hereinbefore is believed to be understandable to those ofordinary skill in the art. Conventional engineering materials andfabrication practices may be used to construct and assemble thecomponents of the generators. Although preferred embodiments have beendescribed in detail herein, those skilled in the art will also recognizethat various substitutions and modifications may be made withoutdeparting from the scope and spirit of the appended claims.

What is claimed is:
 1. A wind driven power generator comprising: aframe; a rotor supported for rotation on said frame, said rotorincluding plural, circumferentially spaced apart elongated, generallyparallel rotor blades, said rotor blades being supported by spaced apartarm assemblies, at least one of said arm assemblies including a hubportion drivingly connected to a drive shaft; wherein said rotorincludes rotor blade lifting force control means having cam followersengageable with a cam operably connected to said rotor blades, whereineach of said rotor blades is connected to a control link connected toone of said cam followers, respectively, and responsive to rotation ofsaid rotor to vary one of the pitch angle and camber of said each rotorblade with respect to the direction of wind impinging on said rotor; andat least one governor mechanism operably linked to said cam, whereinsaid mechanism modulates said rotation by varying one of said pitchangle or camber of said rotor blades.
 2. The wind drive power generatorset forth in claim 1, wherein: said cam followers engage said cam via agroove disposed in said cam.
 3. The wind drive power generator set forthin claim 2, wherein: said cam groove has a longitudinal axis that isoriented at an angle relative to the transverse axis of said cam formingan angled cam groove.
 4. The wind drive power generator set forth inclaim 3, wherein: said governor mechanism alters the position of saidangled cam groove engaging said cam followers to vary one of the pitchangle or camber of each rotor blade.
 5. The wind drive power generatorset forth in claim 2, wherein: said cam groove has a varying surfaceforming a varying cam groove.
 6. The wind drive power generator setforth in claim 5, wherein: said governor mechanism alters the positionof said varying cam groove engaging said cam followers to vary one ofthe pitch angle or camber of each rotor blade.
 7. The wind drive powergenerator set forth in claim 6, wherein: said varying cam grooveincludes at least one angled portion and one transverse portion.
 8. Thewind drive power generator set forth in claim 7, wherein: said governormechanism alters the position of said cam via a linkage.
 9. The winddrive power generator set forth in claim 7, wherein: said governormechanism shift said cam forcing said cam followers to move inwardly andupwardly into said angled groove causing said control means to vary saidrotor blades angle of attack to modulate said rotor rotation.
 10. A winddriven power generator comprising: a frame; a rotor supported forrotation on said frame, said rotor including plural, circumferentiallyspaced apart elongated, generally parallel rotor blades, said rotorblades being supported by spaced apart arm assemblies, at least one ofsaid arm assemblies including a hub portion drivingly connected to adrive shaft; a rotor blade lifting force control means having camfollowers engaging angled cam groove of a cam operably connected to saidrotor blades, each of said rotor blades is connected to a link connectedto one of said cam followers, respectively, and said control means isresponsive to rotation of said rotor to vary one of the pitch angle andcamber of said each rotor blade with respect to the direction of windimpinging on said rotor; and at least one tensioning device positionedbetween said cam and said hub portion.
 11. The wind drive powergenerator set forth in claim 10, wherein: said cam followers engage saidcam via a groove disposed in said cam, wherein said cam groove has alongitudinal axis that is oriented at an angle relative to thetransverse axis of said cam forming an angled cam groove.
 12. The winddrive power generator set forth in claim 11, wherein: said cam groovehas a varying surface forming a varying cam groove.
 13. The wind drivepower generator set forth in claim 12, wherein: said varying cam grooveincludes at least one angled portion and one transverse portion.